sound: Add an ACPI driver for Maxim MAX98357ac
This chip is used on coral and we need to generate ACPI tables for sound
to make it work. Add a driver that does just this (i.e. at present does
not actually support playing sound).
Signed-off-by: Simon Glass <sjg@chromium.org>
[bmeng: Use the correct acpi_irq_polarity enum number]
Signed-off-by: Bin Meng <bmeng.cn@gmail.com>
diff --git a/drivers/sound/max98357a.c b/drivers/sound/max98357a.c
new file mode 100644
index 0000000..841bc6e
--- /dev/null
+++ b/drivers/sound/max98357a.c
@@ -0,0 +1,161 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * max98357a.c -- MAX98357A Audio driver
+ *
+ * Copyright 2019 Google LLC
+ * Parts taken from coreboot
+ */
+
+#include <common.h>
+#include <audio_codec.h>
+#include <dm.h>
+#include <log.h>
+#include <sound.h>
+#include <acpi/acpigen.h>
+#include <acpi/acpi_device.h>
+#include <acpi/acpi_dp.h>
+#include <asm-generic/gpio.h>
+#ifdef CONFIG_X86
+#include <asm/acpi_nhlt.h>
+#endif
+#include <dt-bindings/sound/nhlt.h>
+#include <dm/acpi.h>
+
+struct max98357a_priv {
+ struct gpio_desc sdmode_gpio;
+};
+
+static int max98357a_ofdata_to_platdata(struct udevice *dev)
+{
+ struct max98357a_priv *priv = dev_get_priv(dev);
+ int ret;
+
+ ret = gpio_request_by_name(dev, "sdmode-gpios", 0, &priv->sdmode_gpio,
+ GPIOD_IS_IN);
+ if (ret)
+ return log_msg_ret("gpio", ret);
+
+ return 0;
+}
+
+static int max98357a_acpi_fill_ssdt(const struct udevice *dev,
+ struct acpi_ctx *ctx)
+{
+ struct max98357a_priv *priv = dev_get_priv(dev);
+ char scope[ACPI_PATH_MAX];
+ char name[ACPI_NAME_MAX];
+ char path[ACPI_PATH_MAX];
+ struct acpi_dp *dp;
+ int ret;
+
+ ret = acpi_device_scope(dev, scope, sizeof(scope));
+ if (ret)
+ return log_msg_ret("scope", ret);
+ ret = acpi_get_name(dev, name);
+ if (ret)
+ return log_msg_ret("name", ret);
+
+ /* Device */
+ acpigen_write_scope(ctx, scope);
+ acpigen_write_device(ctx, name);
+ acpigen_write_name_string(ctx, "_HID",
+ dev_read_string(dev, "acpi,hid"));
+ acpigen_write_name_integer(ctx, "_UID", 0);
+ acpigen_write_name_string(ctx, "_DDN",
+ dev_read_string(dev, "acpi,ddn"));
+ acpigen_write_sta(ctx, acpi_device_status(dev));
+
+ /* Resources */
+ acpigen_write_name(ctx, "_CRS");
+ acpigen_write_resourcetemplate_header(ctx);
+ ret = acpi_device_write_gpio_desc(ctx, &priv->sdmode_gpio);
+ if (ret)
+ return log_msg_ret("gpio", ret);
+ acpigen_write_resourcetemplate_footer(ctx);
+
+ /* _DSD for devicetree properties */
+ /* This points to the first pin in the first gpio entry in _CRS */
+ ret = acpi_device_path(dev, path, sizeof(path));
+ if (ret)
+ return log_msg_ret("path", ret);
+ dp = acpi_dp_new_table("_DSD");
+ acpi_dp_add_gpio(dp, "sdmode-gpio", path, 0, 0,
+ priv->sdmode_gpio.flags & GPIOD_ACTIVE_LOW ?
+ ACPI_IRQ_ACTIVE_LOW : ACPI_IRQ_ACTIVE_HIGH);
+ acpi_dp_add_integer(dp, "sdmode-delay",
+ dev_read_u32_default(dev, "sdmode-delay", 0));
+ acpi_dp_write(ctx, dp);
+
+ acpigen_pop_len(ctx); /* Device */
+ acpigen_pop_len(ctx); /* Scope */
+
+ return 0;
+}
+
+/* For now only X86 boards support NHLT */
+#ifdef CONFIG_X86
+static const struct nhlt_format_config max98357a_formats[] = {
+ /* 48 KHz 24-bits per sample. */
+ {
+ .num_channels = 2,
+ .sample_freq_khz = 48,
+ .container_bits_per_sample = 32,
+ .valid_bits_per_sample = 24,
+ .settings_file = "max98357-render-2ch-48khz-24b.dat",
+ },
+};
+
+static const struct nhlt_endp_descriptor max98357a_descriptors[] = {
+ {
+ .link = NHLT_LINK_SSP,
+ .device = NHLT_SSP_DEV_I2S,
+ .direction = NHLT_DIR_RENDER,
+ .vid = NHLT_VID,
+ .did = NHLT_DID_SSP,
+ .formats = max98357a_formats,
+ .num_formats = ARRAY_SIZE(max98357a_formats),
+ },
+};
+
+static int max98357a_acpi_setup_nhlt(const struct udevice *dev,
+ struct acpi_ctx *ctx)
+{
+ u32 hwlink;
+ int ret;
+
+ if (dev_read_u32(dev, "acpi,audio-link", &hwlink))
+ return log_msg_ret("link", -EINVAL);
+
+ /* Virtual bus id of SSP links are the hardware port ids proper. */
+ ret = nhlt_add_ssp_endpoints(ctx->nhlt, hwlink, max98357a_descriptors,
+ ARRAY_SIZE(max98357a_descriptors));
+ if (ret)
+ return log_msg_ret("add", ret);
+
+ return 0;
+}
+#endif
+
+struct acpi_ops max98357a_acpi_ops = {
+ .fill_ssdt = max98357a_acpi_fill_ssdt,
+#ifdef CONFIG_X86
+ .setup_nhlt = max98357a_acpi_setup_nhlt,
+#endif
+};
+
+static const struct audio_codec_ops max98357a_ops = {
+};
+
+static const struct udevice_id max98357a_ids[] = {
+ { .compatible = "maxim,max98357a" },
+ { }
+};
+
+U_BOOT_DRIVER(max98357a) = {
+ .name = "max98357a",
+ .id = UCLASS_AUDIO_CODEC,
+ .of_match = max98357a_ids,
+ .ofdata_to_platdata = max98357a_ofdata_to_platdata,
+ .ops = &max98357a_ops,
+ ACPI_OPS_PTR(&max98357a_acpi_ops)
+};